Ortho Camera

I am trying to set my camera to an orthogonal view. I am not having success. Can someone tell me why this isn't working. In gui\guiTSControl.h this is the Camera Query structure is

struct CameraQuery
{
   CameraQuery()
   {
      ortho = true;
   }

   SimObject*  object;
   F32         nearPlane;
   F32         farPlane;
   F32         fov;
   MatrixF     cameraMatrix;
   
   F32         leftRight;
   F32         topBottom;
   bool        ortho;
   //Point3F position;
   //Point3F viewVector;
   //Point3F upVector;
};

I set ortho to true.

Its used in line 133 in gui/guiTSControl.cc

dglSetFrustum(left, right, bottom, top, mLastCameraQuery.nearPlane, mLastCameraQuery.farPlane, mLastCameraQuery.ortho);

Why is my camera still perspective mode if ortho is set to true. Thanks in advanced.